Assessing Discrimination and Acceptance for Lightness and Chroma During Shade Selection: A Comparison of Dental and Non-Dental Professionals

Abstract

Background/Objectives: Tooth color is key in determining aesthetic appearance during restorative and prosthodontic treatments. To establish a more reliable methodology for shade selection, this study investigated differences in the discrimination and acceptance of tooth color between dental and non-dental professionals, focusing on color attributes such as lightness and chroma. Methods: This study included 30 dentists, 30 dental technicians, 30 patients, and 30 dental students. They were asked to compare pairs of shade tabs with different lightness and chroma from the VITA Toothguide 3D-MASTER^® (VITA Zahnfabrik, Bad Säckingen, Germany). The number of answers in which participants could discriminate color differences (discrimination numbers) and answers in which they could not accept color differences (non-acceptance numbers) were recorded. Statistical analysis was performed using Spearman's rank correlation coefficient, the Mann-Whitney U test, the Kruskal-Wallis test, and multiple regression analysis (p < 0.05). Results: Significant factors influencing lightness discrimination were participant group and age, while those influencing acceptance were subject group and sex. Conclusions: This study revealed differences in the discrimination and acceptance of lightness and chroma between dental and non-dental professionals, particularly concerning lightness. Dental technicians exhibited a higher discrimination ability and stricter acceptance of lightness and chroma, regardless of age. Based on an understanding of these characteristics, appropriate shade selection and adequate communication will be important.

Keywords: chroma; lightness; shade guide; shade selection; tooth color.

Figure 1

Process for the discrimination and acceptance tests (Co: correct answers, Inco: incorrect answers, Ac: acceptable, non-Ac: answers participants would not allow).